Interference checking device for a transfer press

ABSTRACT

The setting of parameters in a transfer press is simplified by inputting pattern information to an interference checker. From the pattern information (stroke of each shaft, slide stroke and the like) the interference checker simulates the movement conditions of the die, fingers, and product shapes to check the interference status. The pattern information is sent to the transfer press. Also, interference is simulated for display or printing before actual press operation is required.

BACKGROUND TO THE PRESENT INVENTION

The present invention relates to an interference checking device thatchecks for interference between the finger, die, and product duringpress operation in a press that has a transfer device in which thestroke and the like of each shaft (advance-return shaft, clamp-unclampshaft, lift-down shaft) can be user-specified using a servo motor or alinear motor as a drive source.

By the movement of a pair of feed bars, a transfer press of the priorart conducts press working by holding and transporting material tosequential working stages. The manufacturers of such transfer pressesprovide an interference chart for the user. The interference chart showsthe relationships between the position of the upper mold (slide) and theposition of the finger (feed bar) during one rotation of the crankangle. In other words, the interference chart is drawn based on theslide stroke of the press and the strokes of each shaft (advance-returnshaft, clamp-unclamp shaft, lift-down shaft) of the transfer device.

Referring to FIG. 5(A), an interference chart of the advance-returnshaft is shown. Referring to FIG. 5(B), an interference chart for theclamp unclamp shaft (and in the case of three-dimensions, the lift-downshaft is added) is shown. Referring to FIG. 5(A), the horizontal axis isthe stroke of the advance-return shaft (transfer feed stroke), and thevertical axis is the slide stroke of the press. The numerical values (0,90, 180, 270) on the inside of the chart represent the crank angles.There are two interference charts (F-CUV1, F-CUV2) due to differentstrokes for the advance-return shaft (transfer feed stroke).

Referring to FIG. 5(B), the horizontal axis is the stroke of theclamp-unclamp shaft (clamp stroke), and the vertical axis is the slidestroke of the press. In a three-dimensional transport in which lift-downmotion is conducted, the interference chart of the clamp-lift shaft hasthe added change in position of the finger (feed bar) during thelift-down motion (C-CUV1). In the case of two-dimensional transport,only the clamp-unclamp direction (C-CUV2) is shown.

Prior to acquiring a transfer press, the user requests from themanufacturer the desired press slide stroke and strokes for each shaftof the transfer device that correspond to the shape of the product to bepress worked. In accordance with the desires of the user, themanufacturer provides the interference charts shown in FIGS. 5(A), 5(B).Based on the interference charts provided by the manufacturer, the userdecides on the die layout and finger shape and manufactures these.However, due to design mistakes and the like, there is the risk ofinterference among the fingers, die and product. Therefore, afteracquiring the transfer press, there the user must conduct its owninterference check by operating the press slide very slowly with the dieand fingers attached.

Transfer devices come in two types. A mechanical type uses the rotationof the crank shaft of the press as the drive source. An electrical typeuses a servo motor or a linear motor as the drive source. In recentyears, due to the rapid advance in electronic devices, the lattertransfer device has become standard. In transfer devices of themechanical type, changing the stroke of each shaft requires thecumbersome process of exchanging mechanical parts such as the cam andthe like. In contrast, transfer devices that use servo motors or linearmotors as the drive source permit the user to specify the length of thestroke of each shaft within a set range. Therefore, the stroke of eachshaft can be changed easily, and a single transfer press can use severaldies.

If, after the acquisition of a transfer press, the user decides on acertain stroke for each shaft of the transfer device, the creation of aninterference chart, which requires a specialized technique, must beagain requested from the manufacturer. This is very complicated.Furthermore, because the actual interference check for the die and thelike is conducted after the manufacture of the die and the like, ifthere is interference, parts such as the die and the like must bereworked to correct the problem. This is extremely time-consuming. Inother words, although the settings (stroke and the like for each shaft)for the transfer device are easily changed, the accompanying check forinterference among the die, fingers, and product must be determinedbased on drawings. As a result, the procedure for determining theoptimal transfer device settings that match the product (die, fingers)is complicated.

OBJECT AND SUMMARY OF THE INVENTION

The object of the present invention is to provide an interferencechecking device for a transfer press in which the interference check isconducted easily by the user.

The invention is an interference checking device for a transfer press.In order to conduct press working by a press that has a transfer device,the interference checking device for a transfer press checks forinterference among fingers, die, and product while taking intoconsideration the slide stroke of the press and strokes for each shaftof the transfer device, comprising: a means for inputting patterninformation, which is formed by transfer information, press information,and mold-related information; a means for storing patterns to store aplurality of pattern information that is inputted from the inputtingmeans; a means for creating an interference chart to create aninterference chart from one of the pattern information that is stored inthe pattern storing means; a means for checking interference todetermine whether or not fingers and dies interfere based on theinterference chart created by the interference chart creating means; ameans for processing output display to process the interference chartcreated by the interference chart creating means and the determinationresults of the interference checking means for output to an outputdevice.

With the above invention, the interference checking device for thetransfer press includes an inputting means for inputting patterninformation based on transfer information (the stroke of each shaft, forexample), press information (slide stroke, for example), andmold-related information (product shape, die shape, finger shape, andthe like). The inputted pattern information is stored in the patternstoring means. Based on at least some of the pattern information storedin the pattern storing means, an interference chart is created. Theinterference checking means determines whether or not there isinterference among the fingers, die, and product. The interference chartthat is created and the determination results of the interferencechecking means is processed by the output display processing means. Theresult is outputted to a display or the like.

Because interference among the fingers, die, and product in the transferpress can be checked in this manner, the user can easily check forinterference based on various pattern information without having toactually manufacture the die.

A further embodiment of invention is an interference checking device fora transfer press as described in above, wherein: from one of the patterninformation stored in the pattern storing means, transfer informationand press information are outputted to the transfer press.

With this embodiment of the invention, of the pattern information thatis stored in the pattern storing means, the transfer information and thepress information are outputted to the transfer press. In other words,the settings for the stroke of each shaft of the transfer press and theslide stroke of the press and the like do not have to be set again inthe transfer press. In addition, the setting values (transferinformation and press information) that have already been checked forinterference can be selected and outputted. Therefore, in addition tothe advantages of the above embodiment of the invention, the setting ofthe transfer press is more easily conducted.

A further embodiment of the invention is an interference checking devicefor a transfer press as described in the above embodiments, wherein: theinterference chart creating means can also create a timing chart; and inaddition, a current crank angle outputted from the press can bedisplayed on the timing chart that is displayed by the output displayprocessing means.

With this embodiment of the invention, while the transfer press ismoving, the current crank angle is displayed on the timing chart thatrepresents the movement of the press slide and the feed bar. Therefore,in addition to the advantages of the inventions of the aboveembodiments, the movement of the transfer press is easy to understand.

The above, and other objects, features, and advantages of the presentinvention will become apparent from the following description read inconjunction with the accompanying drawings, in which like referencenumerals designate the same elements.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a block diagram of an interference checking device that is anembodiment of the present invention.

FIG. 2 is a flow chart for input of pattern information in an embodimentof the present invention.

FIG. 3 is a flow chart for an interference check in an embodiment of thepresent invention.

FIG. 4 is a timing chart showing the current positions of a slide and afeed bar at the current crank angle in an embodiment of the presentinvention.

FIG. 5(A) is an interference chart of fingers and upper mold in thetransfer direction.

FIG. 5(B) is an interference chart of the upper mold with respect to theclamp.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIG. 1, an interference checking device 1 includes a mainbody 100 associated with a transfer press. An inputting means 2, aprinter 3, and a display device 4 are electrically connected to the mainbody through an I/O port 101. The display device is of any convenienttype, including, for example, a CRT display.

Interference checking device 1 in main body 100 is electricallyconnected to the transfer press 200 through the I/O port 101 to permitthe exchange of signals.

Interference checking device 1 can be affixed to the main body (or thecontrol panel) of press 200, or it can be installed remote from press200.

Transfer press 200 has, as its main structural components, a crown 201supporting a slide. 202. A bed 203 supports the base of columns 204supporting crown 201 in its elevated position. A transfer device 205 hasa servo motor, or a linear motor, as its drive source. A feed bar 206 isactuated by transfer device 205. By setting a variety of parameters,transfer device 205 can have a user-specified stroke within a set range.

Inputting means 2 may be based on a personal computer, for example.Inputting means preferably contains a graphics program such as a CADsystem or the like. Pattern information formed from transfer information(stroke of each shaft, for example), press information (slide stroke,for example), and mold related information (product shape, die shape,finger shape, and the like, for example) are inputted through inputtingmeans 2. Data consisting of numerical values such as stroke and the likeare entered as numerical values. Data consisting of product shape, dieshape, finger shape, and the like are entered as shape data by the CADsoftware. This pattern information is stored in a pattern storing means102. The stored pattern information is given ID numbers. Preferably,pattern storing means 102 is capable of storing several sets of patterninformation. Pattern storing means 102 is constructed, for example, fromEPROM or the like which is read-write capable.

An interference chart creating means 103 is included in main body 100.Interference chart creating means creates an interference chart based onone of the sets of pattern information that is stored in pattern storingmeans 102. Interference chart creating means 103 creates an interferencechart based on transfer information and press information of the patterninformation. Interference chart creating means 103 is formed bydescribing in advance computational equations and the like in a computerprogram stored in ROM, for example. An interference checking means 104is included in main body 100. Based on the interference chart created byinterference chart creating means 103 and mold related information(product shape, die shape, finger shape, and the like), interferencechecking is conducted by a simulation of the movements of the product,die, and fingers. In other words, based on the pattern information,interference checking means 104 determines whether or not there isinterference (collisions) among product, die, and fingers when thetransfer press is operated. Interference checking means 104 is formed bydescribing in advance computational equations and the like in a computerprogram that is stored in ROM, for example.

Main body 100 of interference checking device 1 further includes anoutput display processing means 105. Output display processing means 105outputs through the I/O port 101 the interference charts created byinterference chart creating means 103 and the determination results ofinterference checking means 104 to printer 3 and display device 4.Output display processing means 105 is formed by describing in advancecomputational equations and the like in a computer program that isstored in ROM for example. In addition, each of the means describedabove is unified and maintained by a command-select means 106.Alternatively, based on commands that an operator inputs throughinputting means 2, command-select means 106 sends a command signal toeach of the means, and the specified processing is conducted.

Referring to FIG. 2, an input flow chart of pattern information isshown. In order to input pattern information, inputting means 2 selectsan input mode. An input mode is the mode to be used for inputtingpattern information (IS1). By operating keys and the like, patterninformation is inputted (IS2). A certain number of sets of patterninformation are stored in pattern storing means 102 (IS3). After theinputting and storing of pattern information is completed (IS4),processing transitions to an interference checking mode (Part A of FIGS.2 and 3).

Referring to FIG. 3, the interference checking mode, which checks forinterference, is selected (INT. S1). The option is selected of eitherusing pattern information stored in pattern storing means 102 orinputting pattern information (INT. S2). If pattern information is to berecalled from the pattern information stored in pattern storing means102, the ID number identifying the pattern is inputted into inputtingmeans 2. Thereupon, the pattern information for the inputted ID numberis selected from pattern storing means 102 by command-select means 106via I/O port 101. The selected pattern information is sent tointerference chart creating means 103 (INT. S3). Interference chartcreating means 103 produces an interference chart based on the transferinformation and press information from the pattern information (INT.S4). A check for interference is made based on the interference chartthat is created, together with the mold related information from thepattern information (INT.S6). The interference chart that is created andthe results of interference determination are outputted to outputdisplay processing means 105. Information on the selection of the outputdevice (printer 3, display device 4) decided by the user is inputtedfrom inputting device 2 via I/O port 101 to output display processingmeans 105 by command-select means 106. At output display processingmeans 105, the interference chart and determination results areoutputted to an output device specified by the user (INT. S5). Dependingon the mode of implementation, a three-dimensional image of the fingers,die (upper mold) and product is displayed by output display processingmeans 105. Their movements are simulated, and the interferenceconditions are visually confirmed.

Based on the interference determination results, the operator cancorrect the pattern information (INT. S7). If the interferencedetermination results are good, the pattern information is confirmed(INT. S9). This pattern information can be sent to transfer press 200via I/O port 101 (INT. S9). Based on this pattern information, transferpress 200 can move slide 202 and feed bar 206 and the like.

The pattern information can be corrected at any time after it is input.After correction, a new simulation is conducted. In other words, even ifa die and the like are not actually manufactured, the interferencestatus can be easily checked.

Depending on the type of transfer press, the transfer information can beinformation of the entire material delivery device including, forexample, a destack feeder or a leveler feeder or the like.

In order to prevent actual operation of the transfer press and itsperipheral devices at settings where there is interference among thefingers, die, and product, an interlock circuit (not shown) is builtinto a control device.

Furthermore, interference chart creating means 103 can be formed tocreate a timing chart as shown in FIG. 4. The created timing chart isoutputted to output display processing means 105. During the operationof transfer press 200, the current crank angle is inputted intointerference checking device 1 (main body 100) via I/O port 101. Acommand signal is sent by command-select means 106 to output displayprocessing means 105 to display the inputted current crank angle on thetiming chart. Thereupon, referring to FIG. 4, the current crank angle isdisplayed as a line CL on display device 4. Together with the operationof the transfer press, line CL moves to the right of FIG. 5 moment bymoment. By forming interference checking device 1 in this manner, thepositions of slide 202 and feed bar 206 at the current crank angle canbe readily seen. For example, when there is an emergency stoppage oftransfer press 200, the position of each driving part is easily known,and there can be a quick and safe response.

According to the invention in claim 1, the user can easily conductinterference checks when the stroke of the shafts of the transfer deviceor the stroke of the press is changed. Furthermore, because it is notnecessary to actually manufacture the die and the like in order toconduct the interference checks, interference checks can be conductedeven at places separate from the transfer press. Work by several peoplecan be conducted efficiently. In other words, the workload for designingdies and the like is reduced.

According to the invention in claim 2, the data inputted for theinterference check can be sent to the transfer press. As a result, thedata setup for the transfer press is conducted more reliably and easily.According to the invention in claim 3, during transfer press operation,the current positions for the driving parts (slide, feed bar and thelike) are easily known. As a result, when there is an emergency stoppagefor example, there can be a swift and safe response.

Having described preferred embodiments of the invention with referenceto the accompanying drawings, it is to be understood that the inventionis not limited to those precise embodiments, and that various changesand modifications may be effected therein by one skilled in the artwithout departing from the scope or spirit of the invention as definedin the appended claims.

1. An interference checking device for a transfer press comprising: an inputting means for inputting pattern information consisting of transfer information, press information, and mold-related information; pattern storing means for storing a plurality of sets of pattern information from said inputting means; a processor; and a memory storing processing instructions for controlling the processor, the processor operative with the processing instructions to: create an interference chart from one set of said pattern information in said pattern storing means; and check interference to determine whether a product, fingers and dies in said transfer press interfere based on said interference chart; and an output display processing means for producing an output for reproducing said interference chart and determination results of said interference check.
 2. An interference checking device for a transfer press as described in claim 1, wherein transfer information and press information from said one set of said pattern information stored in said pattern storing means can be output to said transfer press.
 3. An interference checking device for a transfer press according to claim 1 wherein: the processor is further operative with the processing instructions to create a timing chart; and said output display processing means can display said timing chart and a current crank angle on said timing chart.
 4. An interference checking device for a transfer press according to claim 3 wherein said timing chart represents movement of a press slide and a feed bar in said transfer press. 